This application relates generally to railway right of way maintenance equipment of the type used to repair and maintain railroad track. More specifically, the present invention relates to an improved arrangement for balancing railway right of way maintenance devices on the track upon which they are working.
Conventional railroad track consists of a plurality of spaced parallel wooden ties to which are attached a pair of spaced rail tie plates. Each tie plate is configured to rest on the upper surface of the tie and includes holes for receiving spikes or screws, as well as a canted seat or a cradle formation for receiving the bottom of the steel rail. Since two rails make up a railroad track, there are a pair of spaced tie plates on each tie. Some of the spikes are used to secure the tie plate on the tie and others are used to secure the base of the rail to the tie plate cradle. Anchors are used to prevent linear movement of the rails relative to the ties.
Over time, components of the railroad require maintenance, such as removal and replacement of ties, tie plates and anchors, for example. The railway maintenance vehicle typically includes a frame which is either self-propelled or towable along the track, and at least one workhead configured to engage the track to perform the maintenance task. Depending on the type of maintenance being conducted, the vehicle may carry bulk supplies such as ties, tie plates and anchors. Further, the amount of bulk carried by the vehicle may change over the duration of the maintenance, such as by removing replacement track parts from the vehicle and applying them to the track, or by adding expended track parts onto the vehicle. Not only does the weight change on the vehicle, but the center of gravity of the vehicle changes when the weight of the bulk changes.
The center of gravity and the balancing characteristics of the vehicle are particularly important when the maintenance vehicle is to be lifted up off the track, and when the maintenance vehicle is to be turned around on the track. Typically, the workhead assembly is located on one side of maintenance vehicle, and in some cases, the maintenance vehicle must be turned around in order to do the maintenance on the other side of the track.
Rotation is accomplished with a turntable, which is an assembly on the vehicle that lifts the vehicle off the track, rotates the vehicle, and sets the vehicle back down on the track, as is known in the art. The turntable is usually positioned generally centrally on the vehicle. When the vehicle is lifted off the track, the operator typically must pivot the vehicle about a pivot point on the turntable, such as by manually pushing or pulling on the vehicle about the turntable. Thus, a balanced maintenance vehicle is important for the cylinder to lift the maintenance vehicle off of the track, with no portion of the vehicle touching the track and/or ground. Further, a balanced maintenance vehicle is important for the operator to be able to more steadily and more effortlessly turn the vehicle around on the turntable. Further, a balanced maintenance vehicle more positively retains the turntable and the maintenance vehicle to the track.
Thus, there is a need for an improved railway maintenance machine for balancing the machine on the track.
There is also a need for an improved railway maintenance machine which can be more steadily and more effortlessly turned around on the turntable by a single operator.